Income taxes - Disclosure of deferred tax balances (Details) - CAD ($) $ in Thousands |
Sep. 30, 2025 |
Sep. 30, 2024 |
Sep. 30, 2023 |
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| Income Taxes [Abstract] | |||
| Deferred tax assets | $ 239,284 | $ 242,567 | |
| Deferred tax liabilities | (71,673) | (21,132) | |
| Deferred tax assets (liabilities) | $ 167,611 | $ 221,435 | $ 74,351 |
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- Definition Income Taxes [Abstract] No definition available.
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- Definition The amounts of income taxes recoverable in future periods in respect of: (a) deductible temporary differences; (b) the carryforward of unused tax losses; and (c) the carryforward of unused tax credits. [Refer: Temporary differences [member]; Unused tax credits [member]; Unused tax losses [member]] Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition The amounts of income taxes payable in future periods in respect of taxable temporary differences. [Refer: Temporary differences [member]] Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition The amount of deferred tax liabilities or assets. [Refer: Deferred tax liabilities; Deferred tax assets] Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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